From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 5 Jan 2014 11:47:10 +0000 (+0200)
Subject: Support sRGB pixelformats through GL_EXT_texture_sRGB
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=5a93cc603eef43617a10b76bc9c19a3272ac1d49

Support sRGB pixelformats through GL_EXT_texture_sRGB
---

diff --git a/extensions/ext_texture_srgb.glext b/extensions/ext_texture_srgb.glext
new file mode 100644
index 00000000..32fddfbd
--- /dev/null
+++ b/extensions/ext_texture_srgb.glext
@@ -0,0 +1 @@
+extension EXT_texture_sRGB
diff --git a/scripts/maketex.py b/scripts/maketex.py
index 04de1d38..4da7866e 100755
--- a/scripts/maketex.py
+++ b/scripts/maketex.py
@@ -13,7 +13,7 @@ def escape(str):
 			result += c
 	return result;
 
-def make_tex(fn, filter="LINEAR", anisotropy=0, wrap=None):
+def make_tex(fn, filter="LINEAR", anisotropy=0, wrap=None, srgb=False):
 	import Image
 
 	img = Image.open(fn)
@@ -24,6 +24,9 @@ def make_tex(fn, filter="LINEAR", anisotropy=0, wrap=None):
 	elif fmt=="L":
 		fmt = "LUMINANCE"
 
+	if srgb:
+		fmt = "S"+fmt
+
 	result = "storage %s %d %d;\n"%(fmt, img.size[0], img.size[1])
 	result += "filter %s;\n"%filter
 	if "MIPMAP" in filter:
@@ -50,6 +53,7 @@ if __name__=="__main__":
 	parser.add_argument("-f", "--filter", choices=["NEAREST", "LINEAR", "MIPMAP"], default="LINEAR", help="Filtering mode")
 	parser.add_argument("-a", "--anisotropy", metavar="NUMBER", help="Maximum anisotropy, 0 = disable")
 	parser.add_argument("-w", "--wrap", choices=["REPEAT", "CLAMP_TO_EDGE", "MIRRORED_REPEAT"], help="Wrapping mode")
+	parser.add_argument("--srgb", action="store_const", const=True, help="Use sRGB color space")
 	parser.add_argument("image")
 
 	args = parser.parse_args()
@@ -62,4 +66,4 @@ if __name__=="__main__":
 	if not out_fn:
 		out_fn = os.path.splitext(args.image)[0]+".tex2d"
 	out = file(out_fn, "w")
-	out.write(make_tex(args.image, filter, args.anisotropy, args.wrap))
+	out.write(make_tex(args.image, filter, args.anisotropy, args.wrap, args.srgb))
diff --git a/source/pixelformat.cpp b/source/pixelformat.cpp
index 26600b33..027ae88c 100644
--- a/source/pixelformat.cpp
+++ b/source/pixelformat.cpp
@@ -32,10 +32,18 @@ void operator>>(const LexicalConverter &conv, PixelFormat &fmt)
 		fmt = BGR;
 	else if(conv.get()=="BGRA")
 		fmt = BGRA;
+	else if(conv.get()=="SRGB")
+		fmt = SRGB;
+	else if(conv.get()=="SRGB_ALPHA")
+		fmt = SRGB_ALPHA;
 	else if(conv.get()=="LUMINANCE")
 		fmt = LUMINANCE;
 	else if(conv.get()=="LUMINANCE_ALPHA")
 		fmt = LUMINANCE_ALPHA;
+	else if(conv.get()=="SLUMINANCE")
+		fmt = SLUMINANCE;
+	else if(conv.get()=="SLUMINANCE_ALPHA")
+		fmt = SLUMINANCE_ALPHA;
 	else
 		throw lexical_error(format("conversion of '%s' to PixelFormat", conv.get()));
 }
@@ -75,16 +83,24 @@ PixelFormat get_base_pixelformat(PixelFormat pf)
 	{
 	case RGB8:
 	case RGB16F:
-	case RGB32F: return RGB;
+	case RGB32F:
+	case SRGB:
+	case SRGB8: return RGB;
 	case RGBA8:
 	case RGBA16F:
-	case RGBA32F: return RGBA;
+	case RGBA32F:
+	case SRGB_ALPHA:
+	case SRGB8_ALPHA8: return RGBA;
 	case LUMINANCE8:
 	case LUMINANCE16F:
-	case LUMINANCE32F: return LUMINANCE;
+	case LUMINANCE32F:
+	case SLUMINANCE:
+	case SLUMINANCE8: return LUMINANCE;
 	case LUMINANCE_ALPHA8:
 	case LUMINANCE_ALPHA16F:
-	case LUMINANCE_ALPHA32F: return LUMINANCE_ALPHA;
+	case LUMINANCE_ALPHA32F:
+	case SLUMINANCE_ALPHA:
+	case SLUMINANCE8_ALPHA8: return LUMINANCE_ALPHA;
 	default: return pf;
 	}
 }
@@ -100,8 +116,10 @@ unsigned get_component_count(PixelFormat pf)
 	case GREEN:
 	case BLUE:
 	case LUMINANCE:
+	case SLUMINANCE:
 		return 1;
 	case LUMINANCE_ALPHA:
+	case SLUMINANCE_ALPHA:
 		return 2;
 	case RGB:
 	case BGR:
@@ -128,6 +146,16 @@ void require_pixelformat(PixelFormat pf)
 	case LUMINANCE_ALPHA32F:
 		{ static Require _req(ARB_texture_float); }
 		break;
+	case SRGB:
+	case SRGB8:
+	case SRGB_ALPHA:
+	case SRGB8_ALPHA8:
+	case SLUMINANCE:
+	case SLUMINANCE8:
+	case SLUMINANCE_ALPHA:
+	case SLUMINANCE8_ALPHA8:
+		{ static Require _req(EXT_texture_sRGB); }
+		break;
 	case BGR:
 	case BGRA:
 		{ static Require _req(EXT_bgra); }
diff --git a/source/pixelformat.h b/source/pixelformat.h
index c232da1e..01f626c4 100644
--- a/source/pixelformat.h
+++ b/source/pixelformat.h
@@ -6,6 +6,7 @@
 #include "gl.h"
 #include <msp/gl/extensions/arb_texture_float.h>
 #include <msp/gl/extensions/ext_bgra.h>
+#include <msp/gl/extensions/ext_texture_srgb.h>
 
 namespace Msp {
 namespace GL {
@@ -27,6 +28,10 @@ enum PixelFormat
 	RGBA8           = GL_RGBA8,
 	RGBA16F         = GL_RGBA16F_ARB,
 	RGBA32F         = GL_RGBA32F_ARB,
+	SRGB            = GL_SRGB_EXT,
+	SRGB_ALPHA      = GL_SRGB_ALPHA_EXT,
+	SRGB8           = GL_SRGB8_EXT,
+	SRGB8_ALPHA8    = GL_SRGB8_ALPHA8_EXT,
 	BGR             = GL_BGR,
 	BGRA            = GL_BGRA,
 	LUMINANCE       = GL_LUMINANCE,
@@ -36,7 +41,11 @@ enum PixelFormat
 	LUMINANCE_ALPHA    = GL_LUMINANCE_ALPHA,
 	LUMINANCE_ALPHA8   = GL_LUMINANCE8_ALPHA8,
 	LUMINANCE_ALPHA16F = GL_LUMINANCE_ALPHA16F_ARB,
-	LUMINANCE_ALPHA32F = GL_LUMINANCE_ALPHA32F_ARB
+	LUMINANCE_ALPHA32F = GL_LUMINANCE_ALPHA32F_ARB,
+	SLUMINANCE         = GL_SLUMINANCE_EXT,
+	SLUMINANCE8        = GL_SLUMINANCE8_EXT,
+	SLUMINANCE_ALPHA   = GL_SLUMINANCE_ALPHA_EXT,
+	SLUMINANCE8_ALPHA8 = GL_SLUMINANCE8_ALPHA8_EXT
 };
 
 void operator>>(const LexicalConverter &, PixelFormat &);